The device operates from a 2 wire high compliance current loop and is suitable for continuous operation from -40C to 150C with supplies up to +20 Vdc. The sensor is designed to remain functional during voltage transients up to +27V. The sensor output format is a current pulse from 7mA to 14mA (the quiescent bias is 7mA) whose rising edge is accurately placed relative to the edges of the target wheel. The pulse width is determined by both target wheel direction and field strength. The output pulse is coded in multiples of a well defined time interval depending on direction and field strength in conformance with industry standards currently being promoted by leading systems manufacturers. Pulse widths corresponding to differential magnetic fields measured at the sensor of B >4mT (normal operation), 2mT